Use elf offset in signal step check.
The function StepIfSignalHandler assumed that the rel_pc passed
to it was actually an elf offset. A new version of clang created a libc.so
that has a load bias, so tests unwinding through a signal handler
would fail on arm. On other ABIs, there is unwind information that could
be used instead, so the unwind still worked.
The fix is to subtract the load bias from the rel_pc to get an elf
offset to pass to the Register StepIfSignalHandler functions. Change all
of the Register funtions to make it clear what the first parameter means.
Add a unit test for this new code. Also, add an offline test for
this case.
Bug: 145683525
Test: Ran unit tests using the new clang and the old clang.
Change-Id: I3e249653b79bcad6d3a56411a7911fde4888e9d6
diff --git a/libunwindstack/tests/ElfTest.cpp b/libunwindstack/tests/ElfTest.cpp
index d227b60..4866345 100644
--- a/libunwindstack/tests/ElfTest.cpp
+++ b/libunwindstack/tests/ElfTest.cpp
@@ -104,6 +104,8 @@
memory_->SetMemory(0x100, &phdr, sizeof(phdr));
}
+ void VerifyStepIfSignalHandler(uint64_t load_bias);
+
MemoryFake* memory_;
};
@@ -281,7 +283,7 @@
ASSERT_EQ(0x101U, elf.GetRelPc(0x1101, &map_info));
}
-TEST_F(ElfTest, step_in_signal_map) {
+void ElfTest::VerifyStepIfSignalHandler(uint64_t load_bias) {
ElfFake elf(memory_);
RegsArm regs;
@@ -290,6 +292,7 @@
ElfInterfaceFake* interface = new ElfInterfaceFake(memory_);
elf.FakeSetInterface(interface);
+ elf.FakeSetLoadBias(load_bias);
memory_->SetData32(0x3000, 0xdf0027ad);
MemoryFake process_memory;
@@ -299,12 +302,20 @@
}
elf.FakeSetValid(true);
- ASSERT_TRUE(elf.StepIfSignalHandler(0x3000, ®s, &process_memory));
+ ASSERT_TRUE(elf.StepIfSignalHandler(0x3000 + load_bias, ®s, &process_memory));
EXPECT_EQ(ERROR_NONE, elf.GetLastErrorCode());
EXPECT_EQ(15U, regs.pc());
EXPECT_EQ(13U, regs.sp());
}
+TEST_F(ElfTest, step_in_signal_map) {
+ VerifyStepIfSignalHandler(0);
+}
+
+TEST_F(ElfTest, step_in_signal_map_non_zero_load_bias) {
+ VerifyStepIfSignalHandler(0x1000);
+}
+
class ElfInterfaceMock : public ElfInterface {
public:
ElfInterfaceMock(Memory* memory) : ElfInterface(memory) {}
diff --git a/libunwindstack/tests/UnwindOfflineTest.cpp b/libunwindstack/tests/UnwindOfflineTest.cpp
index 0d58c09..364101a 100644
--- a/libunwindstack/tests/UnwindOfflineTest.cpp
+++ b/libunwindstack/tests/UnwindOfflineTest.cpp
@@ -1629,4 +1629,72 @@
EXPECT_EQ(0xfffe1d74ULL, unwinder.frames()[10].sp);
}
+TEST_F(UnwindOfflineTest, signal_load_bias_arm) {
+ ASSERT_NO_FATAL_FAILURE(Init("signal_load_bias_arm/", ARCH_ARM));
+
+ Unwinder unwinder(128, maps_.get(), regs_.get(), process_memory_);
+ unwinder.Unwind();
+
+ std::string frame_info(DumpFrames(unwinder));
+ ASSERT_EQ(17U, unwinder.NumFrames()) << "Unwind:\n" << frame_info;
+ EXPECT_EQ(
+ " #00 pc 0029ef9e libunwindstack_unit_test (SignalInnerFunction+10)\n"
+ " #01 pc 0029efa7 libunwindstack_unit_test (SignalMiddleFunction+2)\n"
+ " #02 pc 0029efaf libunwindstack_unit_test (SignalOuterFunction+2)\n"
+ " #03 pc 002a280b libunwindstack_unit_test (unwindstack::SignalCallerHandler(int, "
+ "siginfo*, void*)+10)\n"
+ " #04 pc 00058bd4 libc.so (__restore)\n"
+ " #05 pc 0029f01e libunwindstack_unit_test (InnerFunction+106)\n"
+ " #06 pc 0029f633 libunwindstack_unit_test (MiddleFunction+16)\n"
+ " #07 pc 0029f64b libunwindstack_unit_test (OuterFunction+16)\n"
+ " #08 pc 002a1711 libunwindstack_unit_test (unwindstack::RemoteThroughSignal(int, unsigned "
+ "int)+260)\n"
+ " #09 pc 002a1603 libunwindstack_unit_test "
+ "(unwindstack::UnwindTest_remote_through_signal_Test::TestBody()+10)\n"
+ " #10 pc 002c8fe3 libunwindstack_unit_test (testing::Test::Run()+130)\n"
+ " #11 pc 002c9b25 libunwindstack_unit_test (testing::TestInfo::Run()+184)\n"
+ " #12 pc 002c9e27 libunwindstack_unit_test (testing::TestSuite::Run()+202)\n"
+ " #13 pc 002d193d libunwindstack_unit_test "
+ "(testing::internal::UnitTestImpl::RunAllTests()+660)\n"
+ " #14 pc 002d160b libunwindstack_unit_test (testing::UnitTest::Run()+134)\n"
+ " #15 pc 002de035 libunwindstack_unit_test (IsolateMain+680)\n"
+ " #16 pc 00058155 libc.so (__libc_init+68)\n",
+ frame_info);
+
+ EXPECT_EQ(0xb6955f9eULL, unwinder.frames()[0].pc);
+ EXPECT_EQ(0xf2790ce8ULL, unwinder.frames()[0].sp);
+ EXPECT_EQ(0xb6955fa7ULL, unwinder.frames()[1].pc);
+ EXPECT_EQ(0xf2790ce8ULL, unwinder.frames()[1].sp);
+ EXPECT_EQ(0xb6955fafULL, unwinder.frames()[2].pc);
+ EXPECT_EQ(0xf2790cf0ULL, unwinder.frames()[2].sp);
+ EXPECT_EQ(0xb695980bULL, unwinder.frames()[3].pc);
+ EXPECT_EQ(0xf2790cf8ULL, unwinder.frames()[3].sp);
+ EXPECT_EQ(0xf23febd4ULL, unwinder.frames()[4].pc);
+ EXPECT_EQ(0xf2790d10ULL, unwinder.frames()[4].sp);
+ EXPECT_EQ(0xb695601eULL, unwinder.frames()[5].pc);
+ EXPECT_EQ(0xffe67798ULL, unwinder.frames()[5].sp);
+ EXPECT_EQ(0xb6956633ULL, unwinder.frames()[6].pc);
+ EXPECT_EQ(0xffe67890ULL, unwinder.frames()[6].sp);
+ EXPECT_EQ(0xb695664bULL, unwinder.frames()[7].pc);
+ EXPECT_EQ(0xffe678a0ULL, unwinder.frames()[7].sp);
+ EXPECT_EQ(0xb6958711ULL, unwinder.frames()[8].pc);
+ EXPECT_EQ(0xffe678b0ULL, unwinder.frames()[8].sp);
+ EXPECT_EQ(0xb6958603ULL, unwinder.frames()[9].pc);
+ EXPECT_EQ(0xffe67ac8ULL, unwinder.frames()[9].sp);
+ EXPECT_EQ(0xb697ffe3ULL, unwinder.frames()[10].pc);
+ EXPECT_EQ(0xffe67ad8ULL, unwinder.frames()[10].sp);
+ EXPECT_EQ(0xb6980b25ULL, unwinder.frames()[11].pc);
+ EXPECT_EQ(0xffe67ae8ULL, unwinder.frames()[11].sp);
+ EXPECT_EQ(0xb6980e27ULL, unwinder.frames()[12].pc);
+ EXPECT_EQ(0xffe67b18ULL, unwinder.frames()[12].sp);
+ EXPECT_EQ(0xb698893dULL, unwinder.frames()[13].pc);
+ EXPECT_EQ(0xffe67b48ULL, unwinder.frames()[13].sp);
+ EXPECT_EQ(0xb698860bULL, unwinder.frames()[14].pc);
+ EXPECT_EQ(0xffe67bb0ULL, unwinder.frames()[14].sp);
+ EXPECT_EQ(0xb6995035ULL, unwinder.frames()[15].pc);
+ EXPECT_EQ(0xffe67bd0ULL, unwinder.frames()[15].sp);
+ EXPECT_EQ(0xf23fe155ULL, unwinder.frames()[16].pc);
+ EXPECT_EQ(0xffe67d10ULL, unwinder.frames()[16].sp);
+}
+
} // namespace unwindstack
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/libc.so b/libunwindstack/tests/files/offline/signal_load_bias_arm/libc.so
new file mode 100644
index 0000000..f046624
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/libc.so
Binary files differ
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/libunwindstack_unit_test b/libunwindstack/tests/files/offline/signal_load_bias_arm/libunwindstack_unit_test
new file mode 100644
index 0000000..f460dd6
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/libunwindstack_unit_test
Binary files differ
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/maps.txt b/libunwindstack/tests/files/offline/signal_load_bias_arm/maps.txt
new file mode 100644
index 0000000..165ae49
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/maps.txt
@@ -0,0 +1,4 @@
+b66b7000-b670c000 r--p 0 00:00 0 libunwindstack_unit_test
+b670c000-b69a8000 r-xp 54000 00:00 0 libunwindstack_unit_test
+f23a6000-f23d0000 r--p 0 00:00 0 libc.so
+f23d0000-f2451000 r-xp 29000 00:00 0 libc.so
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/regs.txt b/libunwindstack/tests/files/offline/signal_load_bias_arm/regs.txt
new file mode 100644
index 0000000..e03f8fd
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/regs.txt
@@ -0,0 +1,16 @@
+r0: b69b7c84
+r1: 1
+r2: 1
+r3: 1
+r4: f1e52bd0
+r5: f1e11000
+r6: f1e52bd0
+r7: f1e52a38
+r8: f1e11000
+r9: 5de82a8f
+r10: f1e06030
+r11: f1e6d080
+ip: ffe67a88
+sp: f2790ce8
+lr: b6955fab
+pc: b6955f9e
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/stack0.data b/libunwindstack/tests/files/offline/signal_load_bias_arm/stack0.data
new file mode 100644
index 0000000..d9f23f8
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/stack0.data
Binary files differ
diff --git a/libunwindstack/tests/files/offline/signal_load_bias_arm/stack1.data b/libunwindstack/tests/files/offline/signal_load_bias_arm/stack1.data
new file mode 100644
index 0000000..6011883
--- /dev/null
+++ b/libunwindstack/tests/files/offline/signal_load_bias_arm/stack1.data
Binary files differ